allow setting a null value for Org :report_timezone, which is valid.
allow setting a null value for Org :report_timezone, which is valid.

Endika/metabase,zoowii/metabase,zoowii/metabase,dashkb/metabase,dashkb/metabase,Endika/metabase,jonasdiel/metabase-ptBR,jonasdiel/metabase-ptBR,zoowii/metabase,blueoceanideas/metabase,lukaswelte/metabase,zoowii/metabase,dashkb/metabase,dashkb/metabase,blueoceanideas/metabase,lukaswelte/metabase,Endika/metabase,Endika/metabase,lukaswelte/metabase,zoowii/metabase,lukaswelte/metabase,jonasdiel/metabase-ptBR,blueoceanideas/metabase,jonasdiel/metabase-ptBR,Endika/metabase,jonasdiel/metabase-ptBR,blueoceanideas/metabase,lukaswelte/metabase,dashkb/metabase,blueoceanideas/metabase